YTA. you know what's low rent? actually saying "posh uni," unironically. you can tell you're new money bc anyone who was comfortable with their status would never be so quick to point it out. for real. calling yourself higher class is especially funny bc that's the most classless thing could do lol; you making these distinctions to your friend is the biggest tell that you're not from around here. if you wanna fit in with your posh uni friends, you can't be so hyper-aware of your status. only new money would feel the need to remind everyone that they're somehow superior. it is snobbish, but it also shows way more of your hand than I think you realize. you basically told your buddy you think you're better than him bc you went to a "posh uni" and also, by your own admission, have been lucky. you're in a different situation than him, but telling him you outclass him is pretty gross tbh. it's gauche.